/// <summary>
/// Takes the intermediate geometry data and performs the calculations
/// to convert that into glTF buffers, views, and accessors.
/// </summary>
/// <param name="geomData"></param>
/// <param name="name">Unique name for the .bin file that will be produced.</param>
/// <returns></returns>
private glTFBinaryData processGeometry(GeometryData geom, string name)
{
// TODO: rename this type to glTFBufferMeta ?
glTFBinaryData bufferData = new glTFBinaryData();
glTFBinaryBufferContents bufferContents = new glTFBinaryBufferContents();
foreach (var coord in geom.vertices)
{
float vFloat = Convert.ToSingle(coord);
bufferContents.vertexBuffer.Add(vFloat);
}
foreach (var index in geom.faces)
{
bufferContents.indexBuffer.Add(index);
}
// Prevent buffer duplication by hash checking
string calculatedHash = ManagerUtils.GenerateSHA256Hash(bufferContents);
ManagerUtils.HashSearch hs = new ManagerUtils.HashSearch(calculatedHash);
var match = binaryFileData.Find(hs.EqualTo);
if (match != null)
{
// return previously created buffer metadata
bufferData.vertexAccessorIndex = match.vertexAccessorIndex;
bufferData.indexAccessorIndex = match.indexAccessorIndex;
return(bufferData);
}
else
{
// add a buffer
glTFBuffer buffer = new glTFBuffer();
buffer.uri = name + ".bin";
buffers.Add(buffer);
int bufferIdx = buffers.Count - 1;
/**
* Buffer Data
**/
bufferData.name = buffer.uri;
bufferData.contents = bufferContents;
// TODO: Uncomment for normals
//foreach (var normal in geomData.normals)
//{
// bufferData.normalBuffer.Add((float)normal);
//}
// Get max and min for vertex data
float[] vertexMinMax = Util.GetVec3MinMax(bufferContents.vertexBuffer);
// Get max and min for index data
int[] faceMinMax = Util.GetScalarMinMax(bufferContents.indexBuffer);
// TODO: Uncomment for normals
// Get max and min for normal data
//float[] normalMinMax = getVec3MinMax(bufferData.normalBuffer);
/**
* BufferViews
**/
// Add a vec3 buffer view
int elementsPerVertex = 3;
int bytesPerElement = 4;
int bytesPerVertex = elementsPerVertex * bytesPerElement;
int numVec3 = (geom.vertices.Count) / elementsPerVertex;
int sizeOfVec3View = numVec3 * bytesPerVertex;
glTFBufferView vec3View = new glTFBufferView();
vec3View.buffer = bufferIdx;
vec3View.byteOffset = 0;
vec3View.byteLength = sizeOfVec3View;
vec3View.target = Targets.ARRAY_BUFFER;
bufferViews.Add(vec3View);
int vec3ViewIdx = bufferViews.Count - 1;
// TODO: Add a normals (vec3) buffer view
// Add a faces / indexes buffer view
int elementsPerIndex = 1;
int bytesPerIndexElement = 4;
int bytesPerIndex = elementsPerIndex * bytesPerIndexElement;
int numIndexes = geom.faces.Count;
int sizeOfIndexView = numIndexes * bytesPerIndex;
glTFBufferView facesView = new glTFBufferView();
facesView.buffer = bufferIdx;
facesView.byteOffset = vec3View.byteLength;
facesView.byteLength = sizeOfIndexView;
facesView.target = Targets.ELEMENT_ARRAY_BUFFER;
bufferViews.Add(facesView);
int facesViewIdx = bufferViews.Count - 1;
buffers[bufferIdx].byteLength = vec3View.byteLength + facesView.byteLength;
/**
* Accessors
**/
// add a position accessor
glTFAccessor positionAccessor = new glTFAccessor();
positionAccessor.bufferView = vec3ViewIdx;
positionAccessor.byteOffset = 0;
positionAccessor.componentType = ComponentType.FLOAT;
positionAccessor.count = geom.vertices.Count / elementsPerVertex;
positionAccessor.type = "VEC3";
positionAccessor.max = new List <float>()
{
vertexMinMax[1], vertexMinMax[3], vertexMinMax[5]
};
positionAccessor.min = new List <float>()
{
vertexMinMax[0], vertexMinMax[2], vertexMinMax[4]
};
accessors.Add(positionAccessor);
bufferData.vertexAccessorIndex = accessors.Count - 1;
// TODO: Uncomment for normals
// add a normals accessor
//glTFAccessor normalsAccessor = new glTFAccessor();
//normalsAccessor.bufferView = vec3ViewIdx;
//normalsAccessor.byteOffset = (positionAccessor.count) * bytesPerVertex;
//normalsAccessor.componentType = ComponentType.FLOAT;
//normalsAccessor.count = geom.data.normals.Count / elementsPerVertex;
//normalsAccessor.type = "VEC3";
//normalsAccessor.max = new List<float>() { normalMinMax[1], normalMinMax[3], normalMinMax[5] };
//normalsAccessor.min = new List<float>() { normalMinMax[0], normalMinMax[2], normalMinMax[4] };
//this.accessors.Add(normalsAccessor);
//bufferData.normalsAccessorIndex = this.accessors.Count - 1;
// add a face accessor
glTFAccessor faceAccessor = new glTFAccessor();
faceAccessor.bufferView = facesViewIdx;
faceAccessor.byteOffset = 0;
faceAccessor.componentType = ComponentType.UNSIGNED_INT;
faceAccessor.count = numIndexes;
faceAccessor.type = "SCALAR";
faceAccessor.max = new List <float>()
{
faceMinMax[1]
};
faceAccessor.min = new List <float>()
{
faceMinMax[0]
};
accessors.Add(faceAccessor);
bufferData.indexAccessorIndex = accessors.Count - 1;
bufferData.hashcode = calculatedHash;
return(bufferData);
}
}
public void CloseGeometry()
{
Debug.WriteLine(String.Format("{0} Closing Geometry", formatDebugHeirarchy));
// Create the new mesh and populate the primitives with GeometryData
glTFMesh mesh = new glTFMesh();
mesh.primitives = new List <glTFMeshPrimitive>();
// transfer ordered vertices from vertex dictionary to vertices list
foreach (KeyValuePair <string, GeometryData> key_geom in currentGeom)
{
string key = key_geom.Key;
GeometryData geom = key_geom.Value;
foreach (KeyValuePair <PointInt, int> point_index in geom.vertDictionary)
{
PointInt point = point_index.Key;
geom.vertices.Add(point.X);
geom.vertices.Add(point.Y);
geom.vertices.Add(point.Z);
}
// convert GeometryData objects into glTFMeshPrimitive
string material_key = key.Split('_')[1];
glTFBinaryData bufferMeta = processGeometry(geom, key);
if (bufferMeta.hashcode != null)
{
binaryFileData.Add(bufferMeta);
}
glTFMeshPrimitive primative = new glTFMeshPrimitive();
primative.attributes.POSITION = bufferMeta.vertexAccessorIndex;
primative.indices = bufferMeta.indexAccessorIndex;
primative.material = materialDict.GetIndexFromUUID(material_key);
// TODO: Add normal attribute accessor index here
mesh.primitives.Add(primative);
}
// glTF entity can not be empty
if (mesh.primitives.Count() > 0)
{
// Prevent mesh duplication by hash checking
string meshHash = ManagerUtils.GenerateSHA256Hash(mesh);
ManagerUtils.HashSearch hs = new ManagerUtils.HashSearch(meshHash);
int idx = meshContainers.FindIndex(hs.EqualTo);
if (idx != -1)
{
// set the current nodes mesh index to the already
// created mesh location.
nodeDict[currentNodeId].mesh = idx;
}
else
{
// create new mesh and add it's index to the current node.
MeshContainer mc = new MeshContainer();
mc.hashcode = meshHash;
mc.contents = mesh;
meshContainers.Add(mc);
nodeDict[currentNodeId].mesh = meshContainers.Count - 1;
}
}
geometryStack.Pop();
return;
}